To crimp or not to crimp, & seating depth??????

OK guys, starting to get serious with the .358 Bellm in my Contender.
Two questions.
#1, on bottleneck cartridges, when starting to work up a load do you usually crimp & if so how tight? Do you wait until you get a sweet load & then start messing with crimp pressure to see if you can improve?

#2, where do you start on bullet seating depth? I'm shooting 200 gr Hornady SPs, & have the OAL set so they are just off the rifling. I'm probably .100-.120 off the cannelure. My goal of course is max. velocity @ min pressure. Am I starting in the right place?
Most of my reloading experience for the Contenders is straight walled cartridges, so this is new country for me.

when i was loading for the 257 roberts,7-08,and 30-06 in the encore i never crimped my rounds.i only neck sized the brass and then i would turn it a half turn and put it in the sizing die again.(lee actually recomends this)never had any problems with loose bullets or accuracy...jim257

Thanks Jim, I didn't think a crimp would be neccesary.
Can I ask what the point was in rotating the case 180* when sizing?

according to lee it makes a more consistant and tighter neck if you rotate it and run it in the die again ,ive always did that( even for long guns)...jim257

I do the same thing when seating primers and bullets. With the bullet I seat it about half way, lower the round and rotate it, then finish seating. I have noticed an improvement in accuracy since I began doing this.